Example CloudWatch log entries

This topic presents example log entries.

Example transfer sessions log entries

In this example, an SFTP user connects to a Transfer Family server, uploads a file, then disconnects from the session.

The following log entry reflects an SFTP user connecting to a Transfer Family server.

{
   "role": "arn:aws:iam::500655546075:role/transfer-s3",
   "activity-type": "CONNECTED",
   "ciphers": "chacha20-poly1305@openssh.com,chacha20-poly1305@openssh.com",
   "client": "SSH-2.0-OpenSSH_7.4",
   "source-ip": "52.94.133.133",
   "resource-arn": "arn:aws:transfer:us-east-1:500655546075:server/s-3fe215d89f074ed2a",
   "home-dir": "/test/log-me",
   "ssh-public-key": "AAAAC3NzaC1lZDI1NTE5AAAAIA9OY0qV6XYVHaaOiWAcj2spDJVbgjrqDPY4pxd6GnHl",
   "ssh-public-key-fingerprint": "SHA256:BY3gNMHwTfjd4n2VuT4pTyLOk82zWZj4KEYEu7y4r/0",
   "ssh-public-key-type": "ssh-ed25519",
   "user": "log-me",
   "kex": "ecdh-sha2-nistp256",
   "session-id": "9ca9a0e1cec6ad9d"
}

The following log entry reflects the SFTP user uploading a file into their Amazon S3 bucket.

{
   "mode": "CREATE|TRUNCATE|WRITE",
   "path": "/test/log-me/config-file",
   "activity-type": "OPEN",
   "resource-arn": "arn:aws:transfer:us-east-1:500655546075:server/s-3fe215d89f074ed2a",
   "session-id": "9ca9a0e1cec6ad9d"
}

The following log entries reflect the SFTP user disconnecting from their SFTP session. First, the client closes the connection to the bucket, and then the client disconnects the SFTP session.

{
   "path": "/test/log-me/config-file",
   "activity-type": "CLOSE",
   "resource-arn": "arn:aws:transfer:us-east-1:500655546075:server/s-3fe215d89f074ed2a",
   "bytes-in": "121",
   "session-id": "9ca9a0e1cec6ad9d"
}

{
   "activity-type": "DISCONNECTED",
   "resource-arn": "arn:aws:transfer:us-east-1:500655546075:server/s-3fe215d89f074ed2a",
   "session-id": "9ca9a0e1cec6ad9d"
}

Example log entries for SFTP connectors

This section contains example logs for both a successful and an unsuccessful transfer. Logs are generated to a log group named /aws/transfer/connector-id, where connector-id is the identifier for your SFTP connector. Log entries for SFTP connectors are generated when you run either a StartFileTransfer or StartDirectoryListing command.

This log entry is for a transfer that completed successfully.

{
    "operation": "RETRIEVE",
    "timestamp": "2023-10-25T16:33:27.373720Z",
    "connector-id": "connector-id",
    "transfer-id": "transfer-id",
    "file-transfer-id": "transfer-id/file-transfer-id",
    "url": "sftp://192.0.2.0",
    "file-path": "/remotebucket/remotefilepath",
    "status-code": "COMPLETED",
    "start-time": "2023-10-25T16:33:26.945481Z",
    "end-time": "2023-10-25T16:33:27.159823Z",
    "account-id": "480351544584",
    "connector-arn": "arn:aws:transfer:us-east-1:account-id:connector/connector-id",
    "local-directory-path": "/connectors-localbucket"
    "bytes": 514
}

This log entry is for a transfer that timed out, and thus was not completed successfully.

{
    "operation": "RETRIEVE",
    "timestamp": "2023-10-25T22:33:47.625703Z",
    "connector-id": "connector-id",
    "transfer-id": "transfer-id",
    "file-transfer-id": "transfer-id/file-transfer-id",
    "url": "sftp://192.0.2.0",
    "file-path": "/remotebucket/remotefilepath",
    "status-code": "FAILED",
    "failure-code": "TIMEOUT_ERROR",
    "failure-message": "Transfer request timeout.",
    "account-id": "480351544584",
    "connector-arn": "arn:aws:transfer:us-east-1:account-id:connector/connector-id",
    "local-directory-path": "/connectors-localbucket"
}

This log entry is for a SEND operation that succeeds.

{
    "operation": "SEND",
    "timestamp": "2024-04-24T18:16:12.513207284Z",
    "connector-id": "connector-id",
    "transfer-id": "transfer-id",
    "file-transfer-id": "transfer-id/file-transfer-id",
    "url": "sftp://server-id.server.transfer.us-east-1.amazonaws.com",
    "file-path": "/amzn-s3-demo-bucket/my-test-folder/connector-metrics-us-east-1-2024-01-02.csv",
    "status-code": "COMPLETED",
    "start-time": "2024-04-24T18:16:12.295235884Z",
    "end-time": "2024-04-24T18:16:12.461840732Z",
    "account-id": "255443218509",
    "connector-arn": "arn:aws:transfer:us-east-1:account-id:connector/connector-id",
    "bytes": 275
}

Descriptions for some key fields in the previous log examples.

Example log entries for Key exchange algorithm failures

This section contains example logs where the Key exchange algorithm (KEX) failed. These are examples from the ERRORS log stream for structured logs.

This log entry is an example where there is a host key type error.

{
    "activity-type": "KEX_FAILURE",
    "source-ip": "999.999.999.999",
    "resource-arn": "arn:aws:transfer:us-east-1:999999999999:server/s-999999999999999999",
    "message": "no matching host key type found",
    "kex": "ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,ecdsa-sha2-nistp256-cert-v01@openssh.com,ecdsa-sha2-nistp384-cert-v01@openssh.com,ecdsa-sha2-nistp521-cert-v01@openssh.com,ssh-ed25519,ssh-rsa,ssh-dss"
}

This log entry is an example where there is a KEX mismatch.

{
    "activity-type": "KEX_FAILURE",
    "source-ip": "999.999.999.999",
    "resource-arn": "arn:aws:transfer:us-east-1:999999999999:server/s-999999999999999999",
    "message": "no matching key exchange method found",
    "kex": "diffie-hellman-group1-sha1,diffie-hellman-group14-sha1,diffie-hellman-group14-sha256"
}